Its role is to conduct current. Have solid core and stranding conductor. Materials: copper, aluminum, silver, copper clad steel, aluminum clad steel, copper and aluminum is mainly used. The conductivity of the copper is much better than that aluminum.

2) refractory layer:

Only the fire resistance cable structure. The cable in the fire can withstand a certain period of time, to give people more time to escape.

3) insulation layer:

Coated outside the conductor, its role is to isolate the conductor, bear the corresponding voltage, prevent leakage current.

Insulating materials have varied, some requirements of dielectric coefficient is smaller, to reduce the loss, have flame retardant properties and can resist high temperature, and some require cable in burning or not produce less smoke and harmful gas, some requirements are tolerant of oil, corrosion resistance, while others require soft.

4) shielding layer:

On the outside of the insulating layer, outer protective layer, the electric field and the electromagnetic interference effect is limited.

The main function is to make the cable filled round, stable structure, filling some cable also has water resistance and fire resistance effect. The main material is glass fiber rope, polypropylene rope, asbestos rope, rubber, many types, but requires a major performance is non hygroscopic materials, of course, is not conductive.

6) undersheath:

The role of the inner layer is a protective layer or insulated wire core are not shield armor damage.

The inner protection layer of extruded and wrapped and longitudinal forms. The requirements for high using extruded shape package form, low requirement by wrapping or longitudinal form.

7) armored layer:

Armoured role is to protect the cable without damage. The most common is the armored and steel armour, and aluminium armour, stainless steel tape armoured etc. The main role is to use steel tape armored steel wire armour is mainly compressive, tensile with. According to the size of the cable armouring steel strip thickness is not the same, which are specified in the cable standard.

8) outer sheath:

The protective effect of the outer cable components. There are three main types: plastic, rubber and metal.

Which is the most commonly used plastic PVC plastic, polyethylene plastic, and according to the characteristics of cable with flame retardant, low smoke and low halogen, low smoke halogen-free type etc.